Real-Time Illumination for Two-Level Volume Rendering

  • Andrew Corcoran
  • John Dingliana
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 7431)


We propose improvements to real-time two-level rendering incorporating ray cast shadows and ambient occlusion of 3D volumetric datasets. Our ambient occlusion calculation utilises the same sampling scheme as standard per-voxel Phong shading thus allowing for an extremely computationally efficient rendering in comparison to other ambient occlusion algorithms. Our ray cast shadows technique requires no pre-processing, does not significantly increase memory requirements and is compatible with ray cast volume renderers. We validate these techniques through a number of user experiments. The results indicate that our ambient occlusion method increases the visual information in an image. Meanwhile, ray cast shadows appear to not provide the hypothesised improvement to image understanding, however this raises some interesting implications regarding the practical relevance of shadows in such two-level volume renderings.


Graphic Processing Unit Computer Graphic Volume Rendering Depth Perception Shape Perception 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Andrew Corcoran
    • 1
  • John Dingliana
    • 1
  1. 1.Trinity College DublinIreland

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